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51.
Ana Mafalda RibeiroJosé Miguel Loureiro 《Chemical engineering science》2002,57(9):1621-1626
The system ASC carbon filter/cyanogen chloride was studied by simulation. Three filter configurations and several models, taking into account Langmuir adsorption and second-order reaction between the adsorbed toxic vapour and the active metal on the surface, were developed.The effects of axial dispersion, number of reaction units, film mass transfer units and intraparticle mass transfer resistance on the breakthrough time were studied.Simulation results show that a complex model should be used in order to predict with reasonable accuracy the protection imparted by these filters. 相似文献
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53.
Miguel J. Bagajewicz Vasilios Manousiouthakis 《American Institute of Chemical Engineers》1992,38(11):1769-1800
This article introduces the “state space” conceptual framework to process synthesis, which is used to provide a novel representation of a distillation network as a composite heat- and mass-exchange network. This representation suggests that distillation network synthesis may best be viewed as an interacting heat- and mass-exchange network synthesis problem. In that regard, familiar tools (such as pinch diagrams) from both heat-exchange network (HEN) and mass-exchange network (MEN) synthesis are shown to be of use in arriving at energy-efficient distillation network designs. Examples of propylene-propane and solvent-water separations are used to illustrate the proposed conceptual framework. 相似文献
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55.
The effects of cooking temperature, time and temperature of brine-salting, and temperature of ripening on the behavior of Enterobacteriaceae in Manchego cheese were studied. Fifty lots of cheese from raw ewe's milk manufactured and ripened under different conditions were investigated throughout a 60-day ripening period. Differences in pH values due to temperature-dependent whey retention accounted for the effect of cooking temperature on coliform and fecal coliform counts. Temperature of brine-salting had no effect on Enterobacteriaceae counts, but a significant effect of salting time on Enterobacteriaceae and fecal coliform counts was detected. Ripening temperature was the manufacturing variable with greatest influence (P<.01) on Enterobacteriaceae and coliform counts during the whole curing period. 相似文献
56.
Cruselles Ernesto J. Soriano Miguel Melús José Luis 《Wireless Personal Communications》1998,7(1):69-88
The prime characteristic of spread spectrum modulated signals is that their bandwidth is greater than the information rate. In this way a redundancy is introduced that allows the severe levels of inteference inherent in the transmission of digital information over radio and satellite links to be overcome. Current spread spectrum applications are primarily in military communications; nevertheless, there is growing interest in this technique for third generation mobile radio networks (UMTS, FPLTS, etc.) with open discussion regarding the practicality of using a multiple access system based on spread spectrum techniques (CDMA). However, in order to support as many users in the same bandwidth as other multiple access techniques such as TDMA or FDMA, it is important how to generate large families of sequences that present low cross-correlation. The aim of this paper is to describe a spreading codes generator that can produce a large number of PN sequences with good properties of auto- and cross-correlation. Moreover, the codes generated shows high unpredictability and good statistical behaviour. This also allows the implementation of some features that are common on military networks such as message privacy (increasingly important in commercial networks) without additional cost. The structure presented shows itself to be advantageous for high speed generation of codes at a low cost, low power consumption (allowing longer life for batteries), small size and simplicity of implementation, essential ingredients for commercial equipment. Another attractive feature is its structural parallelism, useful in VLSI implementations. All of these features render it potentially suitable for the implementation of channel bandwidth sharing systems in future wireless personal communications networks. 相似文献
57.
镀锌层银盐黑色钝化工艺 总被引:1,自引:0,他引:1
在含AgNO30.5~1g/L,CrO35~10g/L,H2SO40.5~1ml/L,光泽控制剂10~25mL/L的钝化液中处理镀锌层,可获得结合力良好、光亮的黑色钝化膜。 相似文献
58.
提出了一种相似度的新定义,使双极WAT模型的实现更加简洁明了。增加一个阈值使系统能判别非存储模式或因其信息量过低而无法鉴定的输入模式,阈值的大小与要求的容错能力有关。双极相似度及阈值通过光学方法实现。阈值的光学实现使系统仍具有照明不变性。通过电路实现取及WTA网络的迭代运算。 相似文献
59.
测量了GaAs/AlGaAs多量子阱红外探测器在零偏压、小偏流和大偏压等条件下的光电流谱,并结合理论计算的光跃迁能量讨论了光电流谱的多峰结构和异常增强特性。 相似文献
60.
考虑Hopfield模型中假态之间的布尔逻辑关系,提出利用IPA模型对神经网络中的假态进行抑制,并和原网络的性能进行了比较,结果表明:改进后的网络性能比Hopfield模型和IPA模型均有较大提高。 相似文献